Method of producing compound covering slabs



Aug. 4, 1942. x. SCHURMANN METHOD OF PRODUCING COMPOUND COVERING SLABS Filed Nov. 25, 1939 Patented Aug. 4, 1942 UTED STATES METHOD OF PRODUCING COMPOUND COVERING SLABS Xaver Schiirmann, Meilen, Switzerland, assignor to the firm Invag Aktiengesellschaft,

Untertor, Chur, Switzerland Application November 25, 1939, Serial No. 306,190 In Switzerland October 4, 1939 Claims.

The invention has reference to the production of compound slabs for covering floors and walls and consisting of an artificial slab as base on which a layer of artificial mass which may be applied in a pasty condition and hardens after application, of for instance Xylolite, which is made of a mixture of magnesite, or magnesium oxide; magnesium chloride; and wood dust, is superposed which may be smoothed, treated with a spattle and eventually polished. The artificial mass may be coloured uniformly or varied and may have an addition of asphalt. Compound slabs of this type may be fixed in position by directly placing same in cement mortar.

Several methods are known to produce such slabs. According to one method Xylolite mass is spread out on a Working table; a liquid paste of magnesite is poured on the Xylolite mass and slabs of cement or tiles are pressed into the magnesite paste. After hardening the whole plate is turned over and the surface which was originally at the bottom is smoothed for compressing the plate.

This method presents the disadvantage that the smoothing can only be carried out after the hardening and it is impossible in that state to make slabs dense and Wear resistant by smoothing. A proper smoothing effect is only obtain.- able as long as the Xylolite mass is in a plastic condition. However, as long as this condition prevails the whole plate cannot be turned over as the slabs or tiles would separate themselves from the magnesite layer.

In another method light building slabs, (slabs of earthenware are excluded) are coveredon both sides with layers of Xylolite, whereby the final slab consists of three layers. These slabs are expensive and are subjected to warping owing to the alteration of the volume of the light building slabs and to the difference in the coefficient of expansion of the light building slabs and of the Xylolite layers.

A further method has for its purpose to adapt bricks to being used as slabs for covering floors and walls in coating same on one or both sides with Xylolite mass. The latter is placed in plastic condition and by the aid of moulds on the bricks or slabs of Xylolite are fixed to the bricks by means of an adhesive.

The use of moulds prevents a surface treat ment of the slabs which is uniform over the whole surface and particularly in the corners of the slabs and of the mould. The production of clouded slabs is practically excluded when using moulds (or frames).

Furthermore this method edge bars 4. On the layer 5 earthenware of manufacturing slabs is uneconomical. The glueing of the finished Xylolite slabs requires these slabs to be preliminarily pressed to prevent warping. This step causes a considerable increase in the costs of producing such slabs which frustrates production on a large scale.

It is the object of the method according to the present invention to overcome these drawbacks and to permit the manufacture of cheap com pound slabs for covering floors and walls.

The method according to the invention comprises placing single artificial slabs, for instance slabs of earthenware, fayence, Eternit, hydraulic binding agents and the like on a working table which may be covered by a layer of finely granulated material such as quartz sand, said slabs being separated from each other by small strips made for instance of a rustproof metal, whereupon a continuous layer of an artificial mass, particularly Xylolite, which may have an addition of asphalt, is spread on the slabs, then the mass is smoothed and divided up into areas corresponding to the size of the slabs.

The device for carrying the method into effect comprises a working table, the plate and edge bars of which are made of a non-corrosive material, and small strips of a non-corrosive material for separating the artificial slabs placed on the table.

Two constructional examples of devices for carrying the method into effect .are illustrated on the accompanying drawing, in which Fig. 1 shows a first constructional example in a vertical section,

Fig. 2 shows a second example in section along line IIII in Fig. 3,

Fig. 3 is a longitudinal section along line III-III in Fig. 2, and

Fig. 4 is a plan view.

Referring now to the drawing the device illustrated in Fig. 1 consists of a working table 1 having a width of approximately 50-75 centimetres and a considerable length and supported by cross-beams 2 and feet 3. The table surface is formed by plates of a rustproof metal or other material that is perfectly plane and does not alter its shape under the influence of moisture and is acid resistant. The lateral edges of the table are formed by rustproof, metallic bars 4 and a layer 5 of a dry, finely granulated material, such as quartz sand, is placed on the table l. A plane surface of this layer 5, the height of which is 2-3 millimetres, is obtained by means of a smoothing rule moved along and guided on the slabs is omitted in this case.

6 of suitable size are placed and are distanced from each other by small strips 1 of rustproof metal. The sand layer ensures that slabs the surface of which is not plane are well supported. Upon these slabs a Xylolite mass 8, which may have an addition of asphalt and may be of uniform colour or multicoloured, is spread in the same way as in making a continuous Xylolite floor. In order to render the surface of the Xylolite mass dense (free of pores) and therefore wear resistant this surface is subjected to a treatment with a spattle or smoothed and spattled. By means of movable rotary cutters working in the longitudinal and transversal direction or by other appropriate cutting devices the layer of Xylolite is divided into areas corresponding to the size of the slabs by milling or cutting grooves into the Xylolite layer, so that the compound slabs can be easily and quickly removed by break-- ing the whole plate up along the grooves. This removal is facilitated by the layer of loose quartz sand which separates the earthenware slab from the plate of the working table.

If the earthenware slabs are plane at their lower surface the layer of sand may be dispensed with.

The device illustrated in Figs. 2-4 differs from that shown in Fig. 1 in that the single metal strips are not inserted from above between the earthenware slabs but these metal strips form a unitary structure consisting of a longitudinal strip l and transverse strips I I. The strips pass through gaps of the plate l2 of the working table. These gaps subdivide the plate into a number of individual parts which are supported by girders l3 and supports I 4 fixed to the legs l5. The strips I El, H are supported on rods I 6, at the lower ends of which rollers I! are provided which cooperate with eccentrics l8 mounted on a shaft [9 extending in the longitudinal direction of the table and provided at its ends with cranks 20. In the position shown in Figs. 2 and 3 the strips are in their uppermost position in which the top of the strips l0 and H extends slightly above the upper surface of the earthenware slabs 6. The layer of quartz sand The slabs 6 are inserted in the areas defined by the strips and the Xylolite mass 8 is applied in the same manner as described above with reference to Fig. 1. Then the strips I0, II are lowered by turning the cranks the surface of the Xylolite mass is made dense by acting upon it with the spattle, then the grooves are cut and the finished slabs removed from the working table as described above.

The finished compound slabs are then stapled for drying and after drying and hardening are ground along their side faces to exact and uniform dimensions. The surface may also be ground, however, slabs with surfaces treated by the spattle are in an increased way proof against sliding than ground surfaces.

Instead of earthenware slabs other artificial slabs such as slabs made of hydraulic binding agents of any kind with or without the addition of fillers, Eternit, fayence etc. may be used. Further the Xylolite mass may be spread on the artificial slabs by mechanical means, for instance by rollers, as is for instance known in the manufacture of linoleum.

The Xylolite mass may also be applied to the artificial slabs in several layers, for instance at first a layer of coarse material may be applied and thereafter a layer of fine material. The surface of the earthenware slab may receive a coating, for instance a bituminous coating, to protect it against moisture.

The above described method permits to produce in an economical manner slabs for floors and walls that are warm to walk on and very resistant against use.

I claim:

1. The method of producing compound covering slabs, comprising placing a large number of artificial slabs on a long working table, distancing adjacent slabs from each other by means of thin metal strips, applying one continuous layer of a pasty and hardening artificial mass covering all the artificial slabs, smoothing the surface of said layer before the hardening of the said artificial mass, and subdividing the artificial mass into areas corresponding to the size of the artificial slabs.

2. The method of producing compound covering slabs, comprising placing a large number of artificial slabs on a long working table, distancing adjacent slabs from each other by means of thin metal strips, applying one continuous layer of Xylolite covering all the artificial slabs, smoothing the surface of said layer before the hardening of the Xylolite mass, subdividing the Xylolite mass into areas corresponding to the size of the artificial slabs by cutting grooves into the Xylolite layer, and removing the compound slabs by breaking same off along those grooves.

3. The method of producing compound covering slabs, comprising placing a large number of artificial slabs on a long working table, distancing adjacent slabs from each other by means of thin metal strips, applying one continuous layer of Xylolite covering all the artificial slabs, smoothing the surface of said layer before the hardening of the Xylolite mass, subjecting the surface of the Xylolite layer to a treatment with a spattle to render said surface dense and resistant against wear, subdividing the Xylolite mass into areas corresponding to the size of the artificial slabs by cutting grooves into the Xylolite layer, removing the compound slabs by breaking same off along those grooves, and grinding the sides of the compound slabs to obtain slabs of uniform size.

4. The method of producing compound covering slabs, comprising placing a large number of artificial slabs on a long working table, distancing adjacent slabs from each other by means of thin strips, applying successively several layers of Xylolite to form one continuous coat covering all the artificial slabs, subdividing the Xylolite mass into areas corresponding to the size of the artificial slabs by cutting grooves into the Xylolite layer, and removing the compound slabs by breaking same 01f along those grooves.

5. The method of producing compound covering slabs, comprising placing a large number of artificial slabs, provided with a coat protecting same against moisture, on a long working table, distancing adjacent slabs from each other by means of thin metal strips, applying one continuous layer of Xylolite covering all the artificial slabs, smoothing the surface of said layer before the hardening of the Xylolite mass, and subdividing the Xylolite mass into areas corresponding to the size of the artificial slabs.

. XAVER SCHfiRMANN. 

